title: Assembling and evaluation of new dehydrogenase enzyme electrode probes obtained by electropolymerization of aminobenzine isomers and PQQ on gold, platinum and carbon electrodes.
abstract: Pt, Au and graphite electrodes have been coated by electropolymerization of 1,2-, 1,3-, 1,4-diaminobenzene (DAB) and 4-aminobiphenyl in the presence of PQQ using cyclic voltammetry. The activity of the modified electrodes for the oxidation of paracetamol, ascorbic and uric acid was reduced by approximately 90% as compared to the bare electrodes. Polymerization in the presence 4,5-dihydro-4,5-dioxo-1H-pyrrolo(2,3-f)quinoline-2,7,9-tricarboxilic+ ++ acid, pyrroloquinolinequinone (PQQ) led, after optimization, to electrodes capable of catalysing the electrooxidation of beta-nicotinamide adenine dinucleotide, reduced form (NADH), in the range 10(-4)-10(-2) mol/l with a detection limit of 5 x 10(-5) mol/l. Amperometric measurements of NADH have been carried out at +0.2 V and the efficiency of different electrodes based on different materials has been studied. By co-entrapment of dehydrogenase highly selective enzymes, electrodes for glucose, L-lactate and L-glutamate were obtained. Dehydrogenase substrates such as glucose, lactate and glutamate were measured in the range 5 x 10(-5)-1 x 10(-2) mol/l, with detection limits of 10(-5) and 5 x 10(-6) mol/l, respectively. Probe stability under non-dynamic conditions was evaluated over 2 months. All the probes showed a decrease of 10% over 1 month and a residual activity of 50% over 2 months.
authors.affiliation: Centro C.N.R. di Studio per l'Elettrochimica e la Chimica Fisica delle Interfasi, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Curulli
authors.forename: I
authors.initials: I
authors.lastname: Carelli
authors.forename: O
authors.initials: O
authors.lastname: Trischitta
authors.forename: G
authors.initials: G
authors.lastname: Palleschi
mesh_terms: D000611:Aminobiphenyl Compounds / Q000032:analysis*; D015374:Biosensing Techniques; D002244:Carbon; D003067:Coenzymes / Q000032:analysis; D004563:Electrochemistry; D004795:Enzyme Stability; D005069:Evaluation Studies as Topic; D006046:Gold; D009243:NAD / Q000032:analysis; D010088:Oxidoreductases / Q000032:analysis*; D045542:PQQ Cofactor; D010655:Phenylenediamines / Q000032:analysis*; D010984:Platinum; D011108:Polymers; D015363:Quinolones / Q000032:analysis; D011809:Quinones / Q000032:analysis
chemical_list: D000611:Aminobiphenyl Compounds; D003067:Coenzymes; D010655:Phenylenediamines; D011108:Polymers; D015363:Quinolones; D011809:Quinones; D009243:NAD; C006757:4-biphenylamine; D010984:Platinum; D045542:PQQ Cofactor; D002244:Carbon; D006046:Gold; D010088:Oxidoreductases